For four decades, I have lived with dead presidents. I’ve woken up with them in the morning and thought about them when I went to bed at night. I’ve imagined them in their youth, with their families and friends; I’ve thought about the cadence of their speech, their posture and stride. From LBJ and JFK to my current subjects, Theodore Roosevelt and William Howard Taft, I’ve sought to understand the person behind the public figure.

I spent 10 years writing Team of Rivals: The Political Genius of Abraham Lincoln—on which Steven Spielberg’s film Lincoln is partly based—and every day I imagined Lincoln’s world. I had never seen it realized, however, until I visited the movie’s set, housed in an old pinball-machine factory in Richmond, Va. When production designer Rick Carter opened a door and led me into his rendering of the Lincoln White House, I felt as if I had been transported back in time. Every detail was so lovingly re-created, from the cubbyholes in Lincoln’s desk to the portrait of Andrew Jackson on the office wall, from the carpets to the clocks and candelabras. Here are some of the features to look for in the movie, the elements that lend an unparalleled authenticity to the production.

His Office. Lincoln’s office, which doubled as the Cabinet Room, is at the center of the film. Lincoln would sometimes write little fragments of speeches and tuck them away in the drawers and cubbyholes of his desk. People thought he wrote his speeches at the last minute, but he mulled over themes and sentences for weeks. The desk is also where he kept what he called his “hot letters,” which he would write in moments of anger or frustration and then wait for his emotions to settle, hoping he would never need to send them. The first-edition books atop the desk in Lincoln are books he would have read—The Poetical Works of John Milton and The Biglow Papers. The maps on the wall are those he would have been studying.

His Stride. Lincoln’s singular way of walking, contemporaries observed, gave the impression that his long, gaunt frame needed oiling. He would plod forward in an awkward manner, his hands hanging at his sides or folded behind his back. His step had no spring, his law partner William Herndon recalled. He lifted his whole foot at once and then thrust it down on the ground rather than landing on his heel. “His legs,” another observer noted, “seemed to drag from the knees down, like those of a laborer going home after a hard day’s work.”

His Voice. Although Lincoln’s voice was “thin” and “high pitched,” reporter Horace White recalled, it had “much carrying power” and “could be heard a long distance in spite of the bustle and tumult of the crowd.” While he seemed awkward at first, when he “hit his stride,” White observed, he grew “very impassioned” and “seemed transfigured” by the strength of his words.

His Sense of Humor. Those who knew Lincoln described him as an extraordinarily funny man. Humor was an essential aspect of his temperament. He laughed, he explained, so he did not weep. His “eyes would sparkle with fun,” one old-timer remembered, “and when he had reached the point in his narrative which invariably evoked the laughter of the crowd, nobody’s enjoyment was greater than his.” His ability to counter criticism with humor was legendary. When told that he was two-faced, he instantly responded, “If I had two faces, do you think I’d be wearing this face?”

His Ability to Connect. The White House then was so much more open than it is today. People wanting government jobs would line up by the hundreds outside Lincoln’s office, each with a story to tell: a reason his family needed a clerkship or a job in a post office in order to survive. Lincoln’s secretaries, John Nicolay and John Hay, told him he didn’t have time for these ordinary people. You are wrong, he responded. These are my “public-opinion baths.” They “serve to renew in me a clearer and more vivid image of that great popular assemblage out of which I have sprung.”